history of atoms

Question 1

Dalton

Answer 1

Dalton proposed the idea of the atomic theory in 1803. He stated that each element had its own type of atom. These atoms were very small, solid particles that were indivisible. (a sphere)

Question 2

J.J Thomson

Answer 2

In 1897, physicist J.J. Thomson discovered the electron. He showed atoms as spheres of positive matter, filled with negatively charged electrons. (the plum pudding model). or chocolate chip cookie model

Question 3

Ernest Rutherford

Answer 3

Rutherford shot tiny, positively charged particles at gold foils. Some of the particles bounced back-that showed atoms consisted of empty space, with a few electrons, and the nucleus in the centre.

Question 4

Neil Bohr

Answer 4

Neil Bohr proposed the idea that the electrons that orbit the nucleus had the capability to jump from path to path, like stepping on the rungs of a ladder. (the quantum leap)